How do you simulate an LCD projector where a lamp projects a patterned light onto a surface? (cycles)(cycles)
You can do this with a spotlight using the pretty much the same node setup as you have but with an additional mapping node to position the image.



You also need to be sure to set the spotlight light size to something small or your projected image will look blurry. 



And the result. 



Update:

Here's it working with your blend file, no settings changed: